*{
    font-size: 15px;
}

body{
    background-color: #222;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

h1{
    color: #333;
    font-family: Arial, Helvetica, sans-serif;
    margin: 0;
    padding: 0;
    font-size: 8rem;
    letter-spacing: -0.3rem;
    position: relative;
}

h1::after{
    content: attr(data-spotlight);/* 取html中对应属性的值 */
    color: transparent;
    position: absolute;
    top: 0;
    left: 0;
    clip-path: ellipse(100px 100px at 0% 50%);
    /* -webkit-clip-path: ellipse(100px 100px at 0% 50%); */
    animation: spotlight 5s infinite;
    /* 遮罩 */
    background-image: url(https://images.unsplash.com/photo-1579547621869-0ddb5f237392?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1500&q=80);
    background-size: 150%;
    background-position: center center;
    -webkit-background-clip: text;
    background-clip: text;
}

@keyframes spotlight {
    0%{
        clip-path: ellipse(100px 100px at 0% 50%);
    }
    50%{
        clip-path: ellipse(100px 100px at 100% 50%);
    }
    100%{
        clip-path: ellipse(100px 100px at 0% 50%);
    }
}